1. Field of the Invention
The present invention relates to a substrate, a method of manufacturing a multi-layer substrate, and a satellite broadcasting reception apparatus. More specifically, the present invention relates to a substrate having a pattern layer on a main surface, a multi-layer substrate manufactured with the substrate, and a satellite broadcasting reception apparatus including the multi-layer substrate.
2. Description of the Background Art
As a substrate having a pattern layer on a main surface, a substrate having a pattern formed from copper on a fluoroplastic substrate has conventionally be used, for example.
In the field of a satellite broadcasting reception apparatus (hereinafter, referred to as “Low Noise Block down converter” or “LNB”), for example, as the number of channels for satellite broadcasting and satellite communication is increased and reception from a plurality of satellites prevails, a reception system in which reception has been carried out by a plurality of LNBs tends to be replaced with a system in which reception is carried out by a single LNB. Consequently, the LNB tends to be equipped with a multi-layer substrate.
In manufacturing such an LNB, the substrate sometimes has a special shape such as a trapezoid, from the viewpoint of a smaller size or reduction in weight. For example, in some cases, in forming a pattern such as an interconnection on the main surface in an intermediate step of manufacturing the substrate, a sub substrate connected to a main substrate and serving as registration unit is provided, so that the entire main substrate and sub substrate has a simple shape such as a rectangle.
FIG. 13 is an enlarged view showing one example of a structure around a connection portion connecting the main substrate and the sub substrate described above in a conventional substrate.
Referring to FIG. 13, in a substrate 101, a main substrate 102 is connected to a sub substrate 103 by a connection portion 104. A pattern 106 is formed on main substrate 102 in an area surrounded by a pattern outline 106A. Connection portion 104 is provided with an NC hole 109 of which opening position is controlled by numerical control (NC), in order to guide a separation line between main substrate 102 and sub substrate 103.
With the structure described above, registration of the substrate can be facilitated in forming the pattern described above, and the main substrate can be separated from the sub substrate after the pattern is formed.
On the other hand, the substrate as described above has suffered from the following problems.
From the viewpoint of simplification of the steps and reduction in manufacturing cost, the step of separating the main substrate from the sub substrate described above may be performed with a method not requiring a new apparatus dedicated for that step, for example, manually.
In such a case, however, a separation line 110 may be formed at an unintended position or in an unintended shape such as a stepped shape as shown in FIG. 13, for example.
Japanese Utility Model Laying-Open No. 4-15864 (conventional example 1) discloses a printed board characterized in that conductive patterns are provided on a substrate to be removed (sub substrate) and connected integrally with a metal on a wall surface in perforations.
The conductive patterns in conventional example 1, however, are provided in order to remove plating formed on the wall surface in the perforations in forming through hole plating. That is, conventional example 1 does not disclose a concept to stabilize a position of a separation line between the pattern on the main substrate and the pattern on the sub substrate.